The present invention relates to a magnetic head for an information recording/reproducing apparatus, such as a video tape recorder (VTR), a digital audio tape recorder (DAT), a floppy disk drive (FDD) and the like, which requires high density magnetic recording more particularly to a magnetic head which is suitable for mass-production even if the thickness of the core films defining a track width is varied.
Many kinds of magnetic heads for high density information recording/reproducing apparatus are widely known. For example, there is a magnetic head comprising a magnetic core composed of magnetic thin films which is sandwiched between a pair of non-magnetic substrates and defines a track width. With reference to FIG. 2, a manufacturing process and structure of such a magnetic head will be described. As shown in FIG. 2(A). a non-magnetic substrate 1, for example, crystallized glass or the like, is provided. Laminated films of magnetic material are layered on a surface of the substrate 1 by a thin film forming process, such as a sputtering or the like, so that the thickness of the core films 2 defines a track width as shown in FIG. 2(B). The non-magnetic substrate on which the core films are layered is cut along dotted lines as shown in FIG. 2(B). Thereafter, the divided substrates are layered on one another to form half core blocks 3A and 3B as shown in FIG. 2(C). The half core block 3B is provided with a groove 4 for lead wires. The core blocks 3A and 3B are attached to each other with the core films 2 being aligned with each other, to form a core block 5 as shown in FIG. 2(C). Thus, after cementing an operational gap 6 and a track width are formed. Thereafter, the core block 5 is sliced so that the core film 2 is sandwiched and a head chip 7, as shown in FIG. 2(D). is obtained. The head chip 7 functions as a magnetic core by the core films 2 to define the track width.
In the conventional magnetic head thus constructed, the core films sandwiched between a pair of non-magnetic substrates define the track width. One disadvantage is that the core films of the half core blocks 3A and 3B will be displaced from each other, as shown in FIG. 2(E), if the core film is formed non-uniformly on the non-magnetic substrate or the tracking misalignment errors occur in the attaching process. Another disadvantage is that the thickness of the magnetic thin films can not be selected to achieve the most suitable conditions of the magnetic characteristics.